Cellular explosive charge



(No Model.) H. MAXIM.

CELLULAR EXPLOSIVE CHARGE. I No. 552,919. Patented Jan. 14, 1896.

WITNESSES: M5 fm UNITED STATES PATENT -OFFICE.

enson MAXIM, orrrmsrmm, MASSACHUSETTS.

CELLULAR EXPLOSIVE OHARG s.

srncrsrcsrrou forming part of Letters 2min: No. 552,919, new! Januar 14,1ann

To all whom it may concern.-

Be it known that I, HUDSON MAXIM, residand State of Massachu tts, ave invented certain new and useful mprovements in Cellular Explosive Compounds, of which the following is a specification, reference being-had therein to-theaccompanying drawings.

This invention relates to an explosive compound adapted .for use either as a propellingcharge for a cartridge or the like or as a bursting charge for a shell or projectile, and

when used as a propellingechargeis particularly adapted for throwing high explosives from ordnance.

The object of the present invention is to adapt an amorphous explosive celluloid or colloidal nitro compound for use in mass or bulk,as distinguished from grains or particles, so that such mass or bulk may be utilized as a propelling or bursting charge with equal or more efiectiveness than the granular fprm of such explosive celluloid.

It alsohas for its object to so form this amorphous explosive celluloid, when in bulk or mass form that its combustion or consumption will begin comparatively slow and gradually accelerate or increase as the burning continues by presenting additional or larger areas of burning-surface,whereby high explosives, sensitive to percussion, may be thrown from ordnance with safety; and also produce an amorphous explosive celluloid, which may be used as a bursting charge, having within itself suiiicient elasticity to counteract the liability to detonate where the use of a larger percentage of certain of its ingredients would tend to make it more susceptible to sudden shock.

Ileretofore it hasbecn' attempted to prepare ordinary black granular gunpowder and the like so that its speed of combustion or explosion might be sufliciently lessened by reducing its burning-surface to permit of its being employed to throw high explosives from ordnance with safety; but, so far as experience has demonstrated, such methods have not proved efiicient, no matter how massed or compressed, it being still too quick for such use,for the reason that because of its granular structure, whether it be sub-divided or par-1 Application died 8eptember'24,1889. Swindle-324,908. (Newman-J loidal mass.

titioned or compressed, as the heated gases 1 under the heavypressure exerted by the explosion almost simultaneously penetrate and communicate through the entire mass, andv thereby explode it throughoutits substance, exerting a shock upon the projectile substantially-as great asithough the propelling-charge had not received any special preparation.

The present invention employs an explosive celluloid or colloidal nitro compound in which the distinguishing characteristics are that it is an amorphous, dense, horn-like, solid, col- The peculiarities of this amorphous colloidal mass are that it is capableof partaking any form desired, and unless an undue quantity of nitroglycerine be employed in it, it is absolutely incapable of detonation from shock. Another important characteristic of this compound is that it is not hygroscopic anddoes not deteriorate by time or ex- .posure by variations of temperature and moisture.

This explosive celluloid or colloidal nitrocompound consists in the main of gun-cotton or of gun-cotton and nitroglycerine, any vols? tile solvent employed be ng evaporated out p of the finished product, except in some cases gum-camphor. may employed which is not sufficiently volatile to be readily evaporated. These ingredients,'with or without the gumcamphor, are worked or stirred mechanically until the compound becomes thoroughly gelatinized, or is turned into a more or less plastic mass or colloidal solid, capable of retaining any shape which may be imparted to it, or which may have been imparted to it while in a plastic condition.

In the practice of the present invention I do not employ this amorphous explosive celluloid in grains or granular form resembling ordinary powder, but to use it in its solid or mass form and impart thereto a cellular structure which provides the single mass with a greatly-increased surface with which the flame of combustion may come in direct contact directly as the mass is consumed from its exposed surfaces and no faster without destroying its compact and single-mass form. Such a sin le-mass structure when confined and ignite may be made to present to the small area over which the combustion will take place and which area will be increased and fresh areas presented to theilame until the charge is entirely consumed. In this manner the amorphous and cellular compound as a single mass. may be made to reduce the-initial explosion, so that no danger- 'ous shock is transmit ted tothe high explosive of the projectile, and which propelling charge,

after the first ignition, will be consumed with a gradually-accelerating speed, whereby not only is the combustion of the charge keptup by reason of. the maintenance of the initial pressure upon its first combustion, but the projectile is started easily and thongradnally accelerated in speed until it finally leaves the gun at its maximum velocity.

The invention will be more readily understood byadetaileddcscriptiou thereof, aided by'the accompanying drawings, in which- Figure 1 is a longitudinal central section of one form of the porous, cellular, or spongy explosive celluloid. Fig. 2 is a perspective view showinga sheet of the explosive compound with the cells therein and the manner in which it maybe rolled into compact form. Fig. 3 is fi'ltmgitlldillal section of the roll formed'by said sheet. Fig. lis a detail or diagram of a form of sheet-rolling apparatus by which the explosive celluloid may be formed into a cellular sheet.

In the practice of the present invention I employ ,an amorphous explosive celluloid or colloidal nitro comtpound, formed in the 'main of gun-cotton, or o gun-cotton and nitroglycerine, which becomes thoroughly gelatiniaed or a more .or less plastic mass, and after centain volatile solvents are evaporated out becomes a solid mass, which is peculiarly amorphous, dense, and hornlike. Such explosive.

compound, when in a single mass suflieient to make more or less of a propelling-charge for a cartridge and the like, is incapable of use as such because the surface presented to the flame of combustion is not sufficient to make the explosion rapid enough to maintain the necessary pressure for the practicable throwing of projectiles. In order to enable such a solid amorphous explosive compound to be used in mass form as contradistinguished from grains or particles, I provide this amorphous explosive compound with cells, spaces, corrugations or the like, which impart to the amorphous explosive compound a greatly-increased interior surface, which thus presents to the flame of explosion or combustion a greatly-increased burning-surface,

, which surface increases :as the material is consumed and a necessary pressure is created and maintained, as desired. \Vhere the cells ramify through the interiorof the mass of this amorphous explosive compound, the explosion or combustion wiILbreak the mass up into irregular pieces by degrees, sons to constantly present additional or fresh 0 areas to the fiame' of combustion, always pose additional surfaces thereby increasing tion, and cause an projectile.

ith this cellular explosive celluloid or maintaining orimo'nc than maintainingthe desired to use it in practice, and the cells initial pressure due to its firstki'gniti'on until therein may be produced in avarietyof ways'-- as, for example, by forcing air into'a gelatinous, mass of it while in a plastic condition, or small hollow capsules orbits'ofv sponge may be placed in the viscid mass, or the compound while in a fluid state may-be poured over or onto a plate or. form provided with projections and molded to shape,

tions forming the cells in the mass. Thus in the p'rojec Fig. 1 the cellular or spongy structure-B-of explosive celluloid has the. multiplicity of small cells C, which may have beenfornied by forcing air into the compound before cooling or by embedding hollow capsules or supplying it with a quantity of pieces of sponge, as before described. And,again,theexplosivecelluloid or colloidalnitro compound may have itecellular character imparted to it by forming it-into sheets or a continuous shee t. and thereafter or simultaneously making-depressions or corr'u- A gations in the surface of the-sheet. Thus, as shown in Fig. 14, the compound-is drawn between a pair .of rolls 1 2 the upper. oneof which is provided .With. suitable pro ections '3on its surfacewhiletlie;loweriroll'2;is a plain'one. In passin betweenjhepair oi! rolls 1 2, the

surface o the resulting sheet D is provided with a numberof'; depressions corresponding to the projections onthe roll '1. Of course the characterot' these depressions may be the explosive celluloid it may be rolled up into a cylindrical form, as shown in Fig. 2,;

enough of the sheet being used tomake-a cylinder of the desired diameter and any Suite.

able length suitedfto the purpose for which it is to be used. The sheet D will be rolled so that the depressionsare turned inwardly, the

plain portion of one layer of the sheet under- 'variedwidely. In this cellularshect form of lying the depressions of the-superimposed layer, the exterior surface of the finished cylinder E being unbroken. The cyliuderE- thus provides the cellular structure re 1'9- sented in section in Fig. 3, which when igmted and as it is being consumed and continually breaking up or areas totlie flame,

the

will constantly present orex-' its rapidity of consumpaccelerating pressure upon cellular explosive nit-r0 compound nary powder, as granular powder, may be used, the powder filling the cells, spaces, interstices or depressions of the structure.-

As before stated, the cellular compound irregular pieces,'the pieces being defined by.

the interspersed cells which expose still further additional surfaces to the flame, so that it will burn with accelerating rapidity, and the port-ions toward the rear of the chargewill be successively broken up and similarly consumed.

{lhe cellular compound when in sheet form may be formed in a roll or cylinder E,'Fig. 2, and itself form the cartridge, either for gun or blasting purposes, the cells, or course, being of any size or length, and extending entirely through the sheet, and such cells may form any desirable proportion of the mass.

lating the composition or quality of The porous mass or cylinder may be coated with a waterproof coating of the nitro compound that is difilcult of ignition.

By nieansofthe celliilar structure of this explosive compound any desired quantity of the explosivematerial less than the cubical contents of the chamber of a gun may be made up into a charge.

3y regulating the size and location of the cells in a charge of this amorphous explosive compound, I am able to largely regulate the rapidity of combustion. Thus between reguthe compound and determining its cellular structural character I am able to cover a very large range as to the explosive force of-the'compound, the rapidity of combustion, &c., so that a slow-burning explosive agent may be made for heavy guns, or a quick and powerful dctonator for mines, torpedoes, and the like. The material for the coating or covering can be made very difilcult of ignition. It may be a mere varnish or a coating of considerable thickness. l I am aware that celluloid, practically a noncxplosive substance, has been corrugated for ornamental purposes, and that it accidentally any ordicells or spaces, substantially as and for the has air-bubbles in its mass from being improperly made, but itis obvious that such is not my invention.

\Vhais claimed is- I 1. The herein described explosive colloid charge having in its interior a multiplicity of cells, substantially as and for the purpose described.

2. An explosive colloid charge of the character described having throughoutits structure uniformly arranged cells, substantially as and for the purpose described.

3. The herein described amorphous explosive charge having in its interior a multiplicity of cells, spaces, or depressions, or the like, and a filling of granular gunpowder in said purpose described.

4. The herein described amorphous expl'o-.

sive charge in a single mass having an interior cellular structure composed of a multiplicity of separated cells and eziteriorly coated with a coating of celluloid or varnish difficult of ignition with .respect to the interior amorphous mass, substantially as and for the purpose described.

5. The herein described amorphous explosive charge provided in its interior with a multiplicity of separated cells, depressions, or the like, a filling of granular gunpowder in said cells or depressions and exteriorly cdated with a coating of celluloid or varnish dilficult of ignition with respectv to the interior of the amorphous mass, substantially as and for the purpose described. v

6. An amorphous explosive charge of the :character described in sheets having throughout its structure a multiplicity of uniformly arranged cells, substantially as and for the. purpose described.

f 7. An amorphous explosive charge of the character described in a continuous sheet", having a multiplicity of interior. separated cells therein and" rolled into a cylindrical form, substantially as and for the'purpose. described. 4

' vIn testimony whereof I ailix my signature in presence of two witnesses.

- HUDSON MAXIM.

Witnesses: w

' W. A. BARTLETT,

T; W. JouNsoN. 

